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1.
Oncotarget ; 7(4): 4428-41, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26684239

RESUMEN

In melanoma, the adaptative cell response to BRAF inhibitors includes altered patterns of cytokine production contributing to tumor progression and drug resistance. Among the factors produced by PLX4032-resistant melanoma cell lines, CCL2 was higher compared to the sensitive parental cell lines and increased upon drug treatment. CCL2 acted as an autocrine growth factor for melanoma cells, stimulating the proliferation and resistance to apoptosis. In patients, CCL2 is detected in melanoma cells in tumors and in plasma at levels that correlate with tumor burden and lactate dehydrogenase. Vemurafenib treatment increased the CCL2 levels in plasma, whereas the long-term clinical response was associated with low CCL2 levels.Increased CCL2 production was associated with miRNA deregulation in the resistant cells. miR-34a, miR-100 and miR-125b showed high expression in both resistant cells and in tumor biopsies that were obtained from treated patients, and they were involved in the control of cell proliferation and apoptosis. Inhibition of CCL2 and of the selected miRNAs restored both the cell apoptosis and the drug efficacy in resistant melanoma cells. Therefore, CCL2 and miRNAs are potential prognostic factors and attractive targets for counteracting treatment resistance in metastatic melanoma.


Asunto(s)
Quimiocina CCL2/metabolismo , Resistencia a Antineoplásicos/genética , Indoles/farmacología , Melanoma/genética , MicroARNs/genética , Sulfonamidas/farmacología , Adulto , Anciano , Western Blotting , Estudios de Casos y Controles , Quimiocina CCL2/genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Melanoma/tratamiento farmacológico , Melanoma/metabolismo , Melanoma/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Células Tumorales Cultivadas , Vemurafenib
2.
Oncotarget ; 6(7): 5118-33, 2015 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-25742786

RESUMEN

Dysregulation of receptor tyrosine kinases (RTKs) contributes to several aspects of oncogenesis including drug resistance. In melanoma, distinct RTKs have been involved in BRAF inhibitors (BRAFi) resistance, yet the utility of RTKs expression pattern to identify intrinsically resistant tumors has not been assessed. Transcriptional profiling of RTKs and integration with a previous classification, reveals three robust subtypes in two independent datasets of melanoma cell lines and one cohort of melanoma samples. This classification was validated by Western blot in a panel of patient-derived melanoma cell lines. One of the subtypes identified here for the first time displayed the highest and lowest expression of EGFR and ERBB3, respectively, and included BRAF-mutant tumors all intrinsically resistant to BRAFi PLX4720, as assessed by analysis of the Cancer Cell Line Encyclopedia pharmacogenomic study and by in vitro growth inhibition assays. High levels of EGFR were detected, even before therapy, in tumor cells of one of three melanoma patients unresponsive to BRAFi. Use of different pharmacological inhibitors highlighted the relevance of PI3K/mTOR signaling for growth of this PLX4720-resistant subtype. Our results identify a specific molecular profile of melanomas intrinsically resistant to BRAFi and suggest the PI3K/mTOR pathway as a potential therapeutic target for these tumors.


Asunto(s)
Melanoma/clasificación , Melanoma/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos/genética , Humanos , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo
3.
J Am Acad Dermatol ; 72(1): 37-46, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25446807

RESUMEN

BACKGROUND: Diagnosis and proper management of atypical Spitz tumors in pediatric age are still controversial. OBJECTIVE: We sought to investigate the clinicopathological and molecular features of atypical Spitz tumors in patients aged 18 years or younger. METHODS: We performed a retrospective clinicopathological and fluorescence in situ hybridization study on 50 pediatric atypical Spitz tumors. RESULTS: Parameters that were significantly correlated with a diagnosis of atypical Spitz tumors over Spitz nevus included asymmetry, level IV/V, lack of maturation, solid growth, nuclear pleomorphism, high nuclear-cytoplasmic ratio, atypical and deep mitoses, and more than 6 mitoses/mm(2). In the atypical Spitz tumors group, a significantly higher mitotic rate was observed in prepuberal age (P = .04). The 4-probe fluorescence in situ hybridization melanoma assay did not discriminate atypical Spitz tumors from Spitz nevi. Heterozygous 9p21 loss was found in 3 of 37 cases and homozygous 9p21 loss in 2 of 37 cases. Only 1 child experienced a fatal outcome, showing genetic abnormalities by melanoma fluorescence in situ hybridization probe and a heterozygous 9p21 deletion. LIMITATIONS: The limited number of adverse outcomes did not allow the prognostic analysis of single morphologic features. CONCLUSION: Pediatric atypical Spitz tumors are associated with minimal lethal potential. Atypical Spitz tumors require complete excision and careful follow-up while our data do not support any clinical benefit for the sentinel lymph node biopsy procedure and completion lymphadenectomy.


Asunto(s)
Nevo de Células Epitelioides y Fusiformes/patología , Neoplasias Cutáneas/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos
4.
J Clin Oncol ; 32(23): 2479-85, 2014 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-25002727

RESUMEN

PURPOSE: Cutaneous melanoma incidence is increasing. Most new cases are thin (≤ 1 mm) with favorable prognoses, but survival is nonetheless variable. Our aim was to investigate new prognostic factors and construct a nomogram for predicting survival in individual patients. PATIENTS AND METHODS: Data from 2,243 patients with thin melanoma were retrieved from prospectively maintained databases at six centers. Kaplan-Meier survival and crude cumulative incidences of recurrence were estimated, and competing risks were taken into account. Multivariable Cox regression was used to investigate survival predictors. RESULTS: Median follow-up was 124 months (interquartile range, 106 to 157 months); 12-year overall survival was 85.3% (95% CI, 83.4% to 87.2%). Median times to local, regional, and distant recurrence were 79, 78, and 107 months, respectively. Relapse was significantly related to age, Breslow thickness, mitotic rate (MR), ulceration, lymphovascular invasion (LVI), and regression; incidence was lower and subgroup differences were less marked for distant metastasis than for regional relapse. The worst prognosis categories were age older than 60 years, Breslow thickness more than 0.75 mm, MR ≥ 1, presence of ulceration, presence of LVI, and regression ≥ 50%. Breslow thickness more than 0.75 mm, MR ≥ 1, presence of ulceration, and LVI (all P = .001) were significantly associated with sentinel node positivity. Age, MR, ulceration, LVI, regression, and sentinel node status were independent predictors of survival and were used to construct a nomogram to predict 12-year overall survival. The nomogram was well calibrated and had good discriminative ability (adjusted Harrell C statistic, 0.88). CONCLUSION: Our findings suggest including LVI and regression as new prognostic factors in the melanoma staging system. The nomogram appears useful for risk stratification in clinical management and for recruiting patients to clinical trials.


Asunto(s)
Melanoma/mortalidad , Neoplasias Cutáneas/mortalidad , Adulto , Supervivencia sin Enfermedad , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Nomogramas , Pronóstico , Recurrencia , Medición de Riesgo , Neoplasias Cutáneas/patología , Análisis de Supervivencia , Melanoma Cutáneo Maligno
5.
Cancer Immunol Immunother ; 62(5): 897-908, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23589107

RESUMEN

The frequency and function of regulatory T cells (Tregs) were studied in stage II-III melanoma patients who were enrolled in a phase II randomized trial of vaccination with HLA-A*0201-modified tumor peptides versus observation. The vaccinated patients received low-dose cyclophosphamide (CTX) and low-dose interleukin-2 (IL-2). Tregs were analyzed in the lymph nodes (LNs) of stage III patients who were undergoing complete lymph node dissection and in peripheral blood mononuclear cells (PBMCs) collected before vaccination and at different time points during the vaccination period. The LNs of the vaccinated patients, which were surgically removed after two rounds of vaccination and one dose of CTX, displayed a low frequency of Tregs and a less immunosuppressive environment compared with those of the untreated patients. The accurate time-course analysis of the PBMCs of patients enrolled in the vaccination arm indicated a limited and transient modulation in the frequencies of Tregs in PBMCs collected after low-dose CTX administration and a strong Treg boost in those PBMCs collected after low-dose IL-2 administration. However, a fraction of the IL-2-boosted Tregs was functionally modulated to a Th-1-like phenotype in the vaccinated patients. Moreover, low-dose IL-2 promoted the concomitant expansion of conventional activated CD4(+) T cells. Despite the amplification of Tregs, IL-2 administration maintained or further increased the number of antigen-specific CD8(+) T cells that were induced by vaccination as demonstrated by the ex vivo human leukocyte antigen-multimer staining and IFN-γ ELISpot assays. Our study suggests that the use of CTX as a Treg modulator should be revised in terms of the administration schedule and of patients who may benefit from this drug treatment. Despite the Treg expansion that was observed in this study, low-dose IL-2 is not detrimental to the functional activities of vaccine-primed CD8(+) T cell effectors when used in the inflammatory environment of vaccination.


Asunto(s)
Linfocitos T CD4-Positivos/citología , Ciclofosfamida/uso terapéutico , Antígenos de Histocompatibilidad Clase I/inmunología , Interleucina-2/uso terapéutico , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Adulto , Anciano , Antígenos de Neoplasias/inmunología , Antineoplásicos Alquilantes/uso terapéutico , Linfocitos T CD8-positivos/citología , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Inmunosupresores/uso terapéutico , Inmunoterapia/métodos , Interferón gamma/metabolismo , Leucocitos Mononucleares/citología , Masculino , Melanoma/metabolismo , Persona de Mediana Edad , Fenotipo , Neoplasias Cutáneas/metabolismo , Linfocitos T/citología , Factores de Tiempo
6.
Clin Cancer Res ; 18(23): 6485-96, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23032742

RESUMEN

PURPOSE: The progressive immune dysfunctions that occur in patients with advanced melanoma make them unlikely to efficiently respond to cancer vaccines. A multicenter randomized phase II trial was conducted to test whether immunization with modified HLA class I tumor peptides in the context of adjuvant therapy results in better immunologic responses and improved clinical outcomes in patients with early melanoma (stages IIB/C-III). EXPERIMENTAL DESIGN: Forty-three patients were enrolled to undergo vaccination (n = 22) or observation (n = 21). The vaccine included four HLA-A*0201-restricted modified peptides (Melan-A/MART-1([27L]), gp100([210M]), NY-ESO-1([165V]), and Survivin([97M])) emulsified in Montanide ISA51 and injected subcutaneously in combination with cyclophosphamide (300 mg/m(2)) and low-dose IL-2 (3 × 10(6) IU). The immune responses were monitored using ex vivo IFN-γ-ELISpot, HLA/multimer staining, and in vitro short-term peptide sensitization assays. RESULTS: Vaccination induced a rapid and persistent increase in specific effector memory CD8(+) T cells in 75% of the patients. However, this immunization was not associated with any significant increase in disease-free or overall survival as compared with the observation group. An extensive immunologic analysis revealed a significantly reduced cross-recognition of the corresponding native peptides and, most importantly, a limited ability to react to melanoma cells. CONCLUSIONS: Adjuvant setting is an appealing approach for testing cancer vaccines because specific CD8(+) T cells can be efficiently induced in most vaccinated patients. However, the marginal antitumor activity of the T cells induced by modified peptides in this study largely accounts for the observed lack of benefit of vaccination. These findings suggest reconsidering this immunization strategy, particularly in early disease.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Melanoma/inmunología , Melanoma/patología , Péptidos/inmunología , Linfocitos T/inmunología , Vacunas contra el Cáncer/administración & dosificación , Estudios de Casos y Controles , Reacciones Cruzadas/inmunología , Epítopos de Linfocito T/inmunología , Antígenos de Histocompatibilidad Clase I/química , Humanos , Memoria Inmunológica , Antígeno MART-1/química , Antígeno MART-1/inmunología , Melanoma/mortalidad , Melanoma/terapia , Estadificación de Neoplasias , Resultado del Tratamiento , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunología
8.
J Invest Dermatol ; 131(12): 2448-57, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21796150

RESUMEN

Axl, a member of the TAM (Tyro3, Axl, Mer) family of receptor tyrosine kinases, displays an increasingly important role in carcinogenesis. Analysis of 58 cutaneous melanoma lines indicated that Axl was expressed in 38% of them, with significant overrepresentation in NRAS- compared with BRAF-mutated tumors. Axl activation could be induced by autocrine production of its ligand, Gas6, in a significant fraction of Axl-positive tumors. Pearson's correlation analysis on expression data from five data sets of melanoma lines identified several transcripts correlating positively or negatively with Axl. By functionally grouping genes, those inversely correlated were involved in melanocyte development and pigmentation, whereas those positively correlated were involved in motility, invasion, and microenvironment interactions. Accordingly, Axl-positive melanomas did not express microphthalmia transcription factor (MITF) and melanocyte differentiation antigens (MDAs) such as MART-1 and gp100 and possessed a greater in vitro invasive potential compared with Axl-negative ones. Motility, invasivity, and ability to heal a wound or to migrate across an endothelial barrier were inhibited in vitro by Axl knockdown. Pharmacological inhibition of Axl using the selective inhibitor R428 had comparable effects in reducing migration and invasion. These results suggest that targeted inhibition of Axl signaling in the subset of melanomas lacking MITF and MDAs may represent a novel therapeutic strategy.


Asunto(s)
Antígenos Específicos del Melanoma/metabolismo , Melanoma/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias Cutáneas/metabolismo , Antígenos de Diferenciación/metabolismo , Benzocicloheptenos/farmacología , Línea Celular Tumoral , Movimiento Celular/genética , Inhibidores Enzimáticos/farmacología , Técnicas de Silenciamiento del Gen , Humanos , Melanoma/genética , Melanoma/patología , Antígenos Específicos del Melanoma/genética , Mutación , Invasividad Neoplásica , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Triazoles/farmacología , Tirosina Quinasa del Receptor Axl
9.
Ann Surg ; 252(6): 1052-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21107116

RESUMEN

OBJECTIVE: The purpose of the study was to evaluate the excision margin necessary for desmoplastic melanoma (DM). BACKGROUND: DM consists of 2 histologic subtypes, pure DM (PDM) and mixed DM (MDM), differing in extent of fibrotic component. We investigated clinical and therapeutic determinants of prognosis in these DM entities. METHODS: We reviewed 118 PDM and 124 MDM treated at our Institute over 25 years. Local relapse, distant metastasis, and survival were studied. RESULTS: Most (91.7%) distant metastases in PDM developed after 1 or more local recurrences; whereas distant metastasis usually (79.6%) occurred as first event in MDM. Overall mortality trends in relation to lesion-thickness-plus-excision-width differed for PDM (P = 0.014) but not MDM (P = 0.185). For PDM, 5-year crude cumulative incidence (CCI) of mortality was higher (40.0%) for thin tumors (≤ 2 mm thick) excised with 1 cm margin than those excised with 2 cm (14.8%); CCI of mortality for PDM > 2 mm thick excised with 2 cm margins (13.4%) was similar to that for thin PDM lesions excised with 2 cm (14.8%). CCI of local recurrence was also greater in PDM excised with 1 cm margins. In MDM, mortality increased with stage but was independent of excision width (CCI: 29.4% for ≤ 2 mm/2 cm, 31.3% for ≤ 2 mm/1 cm, and 48.3% for > 2 mm/2 cm); a similar trend was found for MDM distant metastases. CONCLUSIONS: In PDM, limited excision width is associated with significantly greater local recurrence and mortality; treatment should be excision with 2 cm margins even for thin lesions. MDM behaves similarly to other melanomas; treatment should follow guidelines on melanoma management.


Asunto(s)
Melanoma/patología , Recurrencia Local de Neoplasia/patología , Neoplasias Cutáneas/patología , Anciano , Femenino , Fibrosis , Humanos , Masculino , Melanoma/mortalidad , Melanoma/cirugía , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/cirugía , Análisis de Supervivencia
10.
J Invest Dermatol ; 130(7): 1877-86, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20376064

RESUMEN

Melanospheres, the melanoma cells that grow as nonadherent colonies and that show in vitro self-renewing capacity and multipotency, were selected from melanoma specimens or from melanoma cell lines. Melanospheres were highly tumorigenic, and intradermal injections in severe combined immunodeficient (SCID) mice of as few as 100 cells generated tumors that maintained tumorigenic potential into subsequent recipients. Primary and serially transplanted xenografts recapitulated the phenotypic features of the original melanoma of the patient. Melanoma cells cultured in the presence of fetal calf serum (FCS) were also tumorigenic in SCID mice, although with lower efficiency; these xenografts showed a homogeneous phenotype for the expression of melanoma-associated markers, Melan-A/Mart-1, HMB45, and MITF, and contained cells with features of fully differentiated cells. Melanospheres were heterogeneous for the expression of stem cell markers and showed a significantly enhanced expression of the Nanog and Oct3/4 transcription factors when compared with adherent melanoma cells. No direct and unique correlation between any of the examined stem cell markers and in vivo tumorigenicity was found. Taken together, our data provide further evidence on the heterogeneous nature of human melanomas and show that melanospheres and their corresponding tumors, which are generated in vivo in immunocompromised mice, represent a model to investigate melanoma biology.


Asunto(s)
Modelos Animales de Enfermedad , Melanoma/secundario , Ratones SCID , Trasplante de Neoplasias/métodos , Neoplasias Cutáneas/patología , Animales , Biomarcadores de Tumor/metabolismo , Proteínas Sanguíneas/farmacología , Antígeno CD146/metabolismo , Diferenciación Celular/fisiología , Línea Celular Tumoral , Proteínas de Homeodominio/metabolismo , Humanos , Inmunofenotipificación , Técnicas In Vitro , Metástasis Linfática , Melanoma/fisiopatología , Ratones , Proteína Homeótica Nanog , Células Madre Neoplásicas/patología , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Neoplasias Cutáneas/fisiopatología , Esferoides Celulares , Trasplante Heterólogo
11.
Histopathology ; 56(2): 251-62, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20102404

RESUMEN

AIMS: Cutaneous leiomyosarcomas (LMS) are rare in comparison with their deep-seated soft tissue and uterine counterparts, and have been poorly characterized. The aim was to verify whether the clinical behaviour of purely dermal LMS is different from that of LMS with minimal subcutis invasion. METHODS AND RESULTS: Twenty-one purely dermal LMS and 15 dermal LMS with minimal subcutis extension were analysed. Tumours developed in 27 men and nine women (age range 29-91 years); most tumours showed a fasciculated (n = 23), pilar-type (n = 12) and pleomorphic (n = 1) pattern. During the follow-up period (range 2-192, mean 41 months) recurrences occurred in 1/16 (6.2%) of tumours confined to the dermis and in 2/11 (18.1%) tumours with minimal subcutis extension. The three recurrent tumours were high-grade LMS, two of which exhibited myxoid areas. One patient with a pleomorphic dermal LMS with minimal extension into fat developed distant metastases 15 years after diagnosis. CONCLUSIONS: For LMS involving the skin, it is advisable to recognize and indicate in the histopathology report the depth of dermal and/or subcutaneous extension, since even minimal subcutaneous involvement may be associated with late local recurrences and/or distant metastases, and therefore appropriate and long-term follow-up is needed.


Asunto(s)
Leiomiosarcoma/patología , Recurrencia Local de Neoplasia , Neoplasias Cutáneas/patología , Tejido Adiposo/patología , Adulto , Anciano , Anciano de 80 o más Años , Dermis/patología , Femenino , Humanos , Leiomiosarcoma/fisiopatología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Metástasis de la Neoplasia , Piel/patología , Neoplasias Cutáneas/fisiopatología , Tejido Subcutáneo/patología
12.
Cancer Res ; 68(3): 715-23, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18245471

RESUMEN

CCN3/nephroblastoma overexpressed belongs to the CCN family of genes that encode secreted proteins associated with the extracellular matrix (ECM) and exert regulatory effects at the cellular level. Overexpression of CCN3 was shown in metastatic melanoma cells compared with cells of the primary tumor from the same patient. Analysis of short-term cultures from 50 primary and metastatic melanomas revealed a heterogeneous expression pattern of both the 46-kDa full-length cytoplasmic/secreted protein and the 32-kDa nuclear-truncated form. The different protein expression patterns were not associated with gene alterations or polymorphisms. Like the metastatic cells expressing high levels of the 46-kDa CCN3, cells transfected to overexpress CCN3 showed increased adhesion to ECM proteins, whereas inhibition of CCN3 expression by small interfering RNA decreased adhesion to laminin and vitronectin. CCN3 overexpression induced increased expression of laminin and vitronectin integrin receptors alpha 7 beta 1 and alpha v beta 5 by increasing their mRNA production. Moreover, CCN3 secreted by melanoma cells acted as an adhesion matrix protein for melanoma cells themselves. Analysis of CCN3 protein expression with respect to melanoma progression detected the protein in all visceral metastases tested and in most nodal metastases from relapsing patients but in only a few nodal metastases from nonrelapsing patients and cutaneous metastases. Consistently, xenotransplantation in immunodeficient mice showed a higher metastatic potential of melanoma cells overexpressing CCN3. Together, these data indicate a role for CCN3 in melanoma cell interaction with the ECM by regulating integrin expression, resulting in altered cell adhesion and leading melanoma progression to aggressive disease.


Asunto(s)
Proteínas Inmediatas-Precoces/fisiología , Integrinas/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/fisiología , Melanoma/patología , Animales , Adhesión Celular/fisiología , Línea Celular Tumoral , Factor de Crecimiento del Tejido Conjuntivo , Progresión de la Enfermedad , Femenino , Humanos , Proteínas Inmediatas-Precoces/biosíntesis , Proteínas Inmediatas-Precoces/genética , Inmunohistoquímica , Integrinas/genética , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/genética , Melanoma/genética , Melanoma/metabolismo , Ratones , Ratones SCID , Proteína Hiperexpresada del Nefroblastoma , Análisis de Secuencia por Matrices de Oligonucleótidos , Transfección
13.
J Clin Oncol ; 24(27): 4464-71, 2006 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-16983115

RESUMEN

PURPOSE: To evaluate the prognostic significance of sentinel node biopsy in the management of stage IB and II melanoma patients, and to evaluate the status of nonsentinel nodes as a "second step key factor" to assess the prognosis of these patients. PATIENTS AND METHODS: We conducted an analysis of data collected in a prospective database. RESULTS: From February 1994 to June 2005, 1,108 consecutive patients with stage IB and II melanoma were submitted to sentinel node biopsy; 176 patients (15.9%) had occult node metastases. The frequency of positive nodes increased with increasing Breslow's thickness. The largest diameter of metastatic foci and their localization within the lymph node were associated with the risk of nonsentinel node metastases only. The 5-year survival of patients with positive sentinel nodes was 81.4% in patients with one positive node and 39.6% in patients with two positive nodes (P = .056). Multivariate analysis indicated that status of sentinel nodes is a key factor and that sex and Breslow's thickness maintain statistically significant relevance. Ulceration, which was associated with survival when considered as single factor (P < .001) had no impact on survival in the multivariate analysis (P = .10). To evaluate the relevance of metastases to nonsentinel nodes, we identified four groups of patients. CONCLUSION: Evaluation of the sentinel node is a useful procedure to identify patients to be submitted for complete lymph node dissection. The procedure makes it possible to assess the best prognosis of patients.


Asunto(s)
Ganglios Linfáticos/patología , Melanoma/secundario , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/patología , Adulto , Bases de Datos Factuales , Femenino , Humanos , Modelos Logísticos , Ganglios Linfáticos/diagnóstico por imagen , Metástasis Linfática , Masculino , Melanoma/cirugía , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Cintigrafía , Neoplasias Cutáneas/cirugía , Análisis de Supervivencia
14.
Phys Med Biol ; 50(8): 1675-87, 2005 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-15815089

RESUMEN

The aim of this research was to evaluate the performance of a new spectroscopic system in the diagnosis of melanoma. This study involves a consecutive series of 1278 patients with 1391 cutaneous pigmented lesions including 184 melanomas. In an attempt to approach the 'real world' of lesion population, a further set of 1022 not excised clinically reassuring lesions was also considered for analysis. Each lesion was imaged in vivo by a multispectral imaging system. The system operates at wavelengths between 483 and 950 nm by acquiring 15 images at equally spaced wavelength intervals. From the images, different lesion descriptors were extracted related to the colour distribution and morphology of the lesions. Data reduction techniques were applied before setting up a neural network classifier designed to perform automated diagnosis. The data set was randomly divided into three sets: train (696 lesions, including 90 melanomas) and verify (348 lesions, including 53 melanomas) for the instruction of a proper neural network, and an independent test set (347 lesions, including 41 melanomas). The neural network was able to discriminate between melanomas and non-melanoma lesions with a sensitivity of 80.4% and a specificity of 75.6% in the 1391 histologized cases data set. No major variations were found in classification scores when train, verify and test subsets were separately evaluated. Following receiver operating characteristic (ROC) analysis, the resulting area under the curve was 0.85. No significant differences were found among areas under train, verify and test set curves, supporting the good network ability to generalize for new cases. In addition, specificity and area under ROC curve increased up to 90% and 0.90, respectively, when the additional set of 1022 lesions without histology was added to the test set. Our data show that performance of an automated system is greatly population dependent, suggesting caution in the comparison with results reported in the literature. In our opinion, scientific reports should provide, at least, the median values of thickness and dimension of melanomas, as well as the number of small (6 mm) melanomas.


Asunto(s)
Inteligencia Artificial , Diagnóstico por Computador/métodos , Análisis de Falla de Equipo , Melanoma/diagnóstico , Reconocimiento de Normas Patrones Automatizadas/métodos , Neoplasias Cutáneas/diagnóstico , Análisis Espectral/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Masculino , Melanoma/clasificación , Persona de Mediana Edad , Redes Neurales de la Computación , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias Cutáneas/clasificación
16.
Oncogene ; 23(35): 5968-77, 2004 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-15195137

RESUMEN

To evaluate the mutational profiles associated with BRAF mutations in human melanoma, we have studied BRAF, RAS, PTEN, TP53, CDKN2A and CDK4 genes and their expression in melanoma lesions. Owing to the lack of sufficient material from fresh specimens, we employed short-term cell lines obtained from melanoma biopsies. In all, 41 melanoma obtained from eight primary lesions, 20 nodal, 11 cutaneous and two visceral metastases from patients with sporadic (n=31), familial (n=4) and multiple melanoma (n=2) were analysed. The results revealed novel missense mutations in the BRAF, PTEN, CDKN2A and CDK4 genes. Overall, activating mutations of BRAF and loss of functional p16 and ARF were detected in the majority of melanomas (29/41, 36/41 and 29/41, respectively), while PTEN alterations/loss, NRAS and TP53 mutations occurred less frequently (6/41, 6/41 and 10/41, respectively). In the resulting 12 mutational profiles, p16/ARF loss associated with mutated BRAFV599E was the most represented (n=15). In addition, TP53 and PTEN mutations were always accompanied with BRAF alterations, while PTEN loss was found in association with CDKN2A or TP53 mutations in the absence of BRAF activation. The p16/ARFDelta+BRAF/RAS profile was significantly associated with a longer survival, while complex mutational profiles were detected in highly aggressive disease and poor survival. These data support the existence of several molecularly defined melanoma groups which likely reflect different clinical/biological behaviour, thus suggesting that a more extensive molecular classification of melanoma would significantly impact its clinical management.


Asunto(s)
Melanoma/genética , Mutación , Proteínas Proto-Oncogénicas c-raf/genética , Proteínas Proto-Oncogénicas , Adulto , Anciano , Anciano de 80 o más Años , Quinasa 4 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/genética , Femenino , Genes p16 , Genes p53 , Humanos , Masculino , Melanoma/etiología , Melanoma/mortalidad , Persona de Mediana Edad , Fosfohidrolasa PTEN , Monoéster Fosfórico Hidrolasas/genética , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas B-raf , Proteínas Supresoras de Tumor/genética
17.
Tumori ; 90(1): 128-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15143985

RESUMEN

BACKGROUND AND AIMS: Very small pigmented lesions may represent an extreme diagnostic challenge to the clinician. Our aim was to describe the clinical and dermoscopic features in a series of cutaneous melanomas with a maximum clinical diameter of 3 mm. METHODS: We conducted a retrospective study of the 924 primary melanomas seen and treated during a period of five years at the Unit for Melanoma Detection of the Istituto Nazionale Tumori of Milan, Italy. The size characteristics of the considered lesions allowed the identification of 22 (2.4%) cases of micro-melanoma (clinical diameter of 3 mm or less). Sixteen of these cases were subjected to dermoscopy. The clinical and dermoscopic features as well as the corresponding diagnoses were recorded. RESULTS: The typical lesion presents as a small, dark, often black macule, generally evenly colored, with well-defined borders; it may be asymmetric or symmetric in shape. These features prompted a correct clinical diagnosis in nearly half of the cases. Dermoscopy lead to a correct diagnosis in all cases subjected to the technique. CONCLUSION: Dermoscopy appears to be an efficient aid to the diagnosis of micro-melanomas, provided that clinicians are aware of this type of lesion and maintain the index of suspicion at a high level.


Asunto(s)
Melanoma/diagnóstico , Neoplasias Cutáneas/diagnóstico , Adulto , Anciano , Dermatología/métodos , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Cutáneas/patología
19.
Med Phys ; 30(2): 212-21, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12607839

RESUMEN

Our aim in the present research is to investigate the diagnostic performance of artificial neural networks (ANNs) applied to multispectral images of cutaneous pigmented skin lesions as well as to compare this approach to a standard traditional linear classification method, such as discriminant function analysis. This study involves a series of 534 patients with 573 cutaneous pigmented lesions (132 melanomas and 441 nonmelanoma lesions). Each lesion was analyzed by a telespectrophotometric system (TS) in vivo, before surgery. The system is able to acquire a set of 17 images at selected wavelengths from 400 to 1040 nm. For each wavelength, five lesion descriptors were extracted, related to the criteria of the ABCD (for asymmetry, border, color, and dimension) clinical guide for melanoma diagnosis. These variables were first reduced in dimension by the use of factor analysis techniques and then used as input data in an ANN. Multivariate discriminant analysis (MDA) was also performed on the same dataset. The whole dataset was split into two independent groups: i.e., train (the first 400 cases, 95 melanomas) and verification set (last 173 cases, 37 melanomas). Factor analysis was able to summarize the data structure into ten variables, accounting for at least 90% of the original parameters variance. After proper training, the ANN was able to classify the population with 80% sensitivity, 72% specificity, and 78% sensitivity, 76% specificity for the train and validation set, respectively. Following ROC analysis, area under curve (AUC) was 0.852 (train) and 0.847 (verify). Sensitivity and specificity values obtained by the standard discriminant analysis classifier resulted in a figure of 80% sensitivity, 60% specificity and 76% sensitivity, 57% specificity for the train and validation set, respectively. AUC for MDA was 0.810 and 0.764 for the train and verify set, respectively. Classification results were significantly different between the two methods both for diagnostic scores and model stability, which was worse for MDA.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Melanoma/clasificación , Melanoma/diagnóstico , Redes Neurales de la Computación , Espectrofotometría/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Diagnóstico por Computador/métodos , Análisis Factorial , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Melanoma/patología , Persona de Mediana Edad , Reconocimiento de Normas Patrones Automatizadas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias Cutáneas/clasificación , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología
20.
Dermatology ; 205(4): 362-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12444332

RESUMEN

BACKGROUND: Successful treatment of melanoma depends directly on early diagnosis. Such a diagnosis is based on clinical examination and dermatoscopy. Recently, automated instruments for melanoma detection are under development. OBJECTIVE: To prospectively evaluate the diagnostic possibilities provided by clinical and dermatoscopic examinations and by a computerized telespectrophotometric system (TS). METHODS: The study involves a consecutive series of 298 patients with 313 cutaneous pigmented lesions (66 melanomas and 247 non-melanoma lesions). Each lesion was subjected to the triple diagnostic evaluation, before surgery. Results were expressed in terms of sensitivity and specificity of each kind of evaluation. RESULTS: Clinical evaluation had sensitivity and specificity values of 86 and 77%, respectively, whereas dermatoscopy gave corresponding values of 91 and 74%. TS assessment resulted in a sensitivity of 80% and a specificity of 49%. Differences between clinical and dermatoscopic diagnoses lacked statistical significance (p = 0.22), whereas there was a significant difference comparing both clinical and TS evaluations (p < 0.01) and dermatoscopic and TS evaluations (p < 0.01). Combining clinical and dermatoscopic evaluations, a sensitivity of 97% was achieved. Addition of TS has not changed this figure. CONCLUSIONS: Results of this study confirm and stress the importance of dermatoscopy in the diagnosis of melanoma. Clinical evaluation coupled with dermatoscopy can be considered the cornerstone of such a diagnosis. Although TS is able to achieve interesting results, at present it cannot significantly compete with any of the other tested methods.


Asunto(s)
Dermatología/instrumentación , Diagnóstico por Computador , Melanoma/patología , Nevo Pigmentado/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Niño , Estudios de Cohortes , Diagnóstico Diferencial , Femenino , Humanos , Italia , Masculino , Melanoma/diagnóstico , Persona de Mediana Edad , Nevo Pigmentado/diagnóstico , Examen Físico/métodos , Estudios Prospectivos , Sensibilidad y Especificidad , Neoplasias Cutáneas/diagnóstico , Espectrofotometría/métodos
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